[PATCH] arm64: dts: mediatek: mt8186: fix clock names for power domains

Alexandre Mergnat amergnat at baylibre.com
Tue Oct 10 05:31:48 PDT 2023


Reviewed-by: Alexandre Mergnat <amergnat at baylibre.com>

On 05/10/2023 12:30, Eugen Hristev wrote:
> Clocks for each power domain are split into big categories: pd clocks 
> and subsys clocks. According to the binding, all clocks which have a 
> dash '-' in their name are treated as subsys clocks, and must be placed 
> at the end of the list. The other clocks which are pd clocks must come 
> first. Fixed the naming and the placing of all clocks in the power 
> domains. For the avoidance of doubt, prefixed all subsys clocks with the 
> 'subsys' prefix. The binding does not enforce strict clock names, the 
> driver uses them in bulk, only making a difference for pd clocks vs 
> subsys clocks. The above problem appears to be trivial, however, it 
> leads to incorrect power up and power down sequence of the power 
> domains, because some clocks will be mistakenly taken for subsys clocks 
> and viceversa. One consequence is the fact that if the DIS power domain 
> goes power down and power back up during the boot process, when it comes 
> back up, there are still transactions left on the bus which makes the 
> display inoperable. Some of the clocks for the DIS power domain were 
> wrongly using '_' instead of '-', which again made these clocks being 
> treated as pd clocks instead of subsys clocks.

-- 
Regards,
Alexandre



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